Did you mean the USB input? Or are you using the I2S input (the value and use of which eludes me as it is such a specialized input and doesn't support HDMI even though the connectivity is the same)... ?
For the second part of you question : i have 3 devices connected to the usb/spdif converter : 1 external recorder via coax, 1 dac via hdmi (computer sabaj) and one dac on the other side of the room in my audio/video setup via AES.
In order to be able to play DSD i have to use the hdmi connection input on the Sabaj. Via the remaining optical only dsd 64 is supported via the usb/spdif device.
The Sabaj shows correct sample rates when connected via usb direct to the computer playing both dop and native DSD. However due to my setup it's not practical to change cables everytime i want to listen to DSD.